Intelligent control heat source heat exchange system

Abstract

The application provides a heat source heat exchange system with intelligent control, a first pipeline is connected between the upstream of a first valve of an inlet branch and the upstream of an outlet valve of an outlet branch, a pipeline valve is arranged on the first pipeline; the system further comprises a heat exchanger pipeline, a heat exchanger is arranged on the heat exchanger pipeline, one end of the heat exchanger pipeline is connected to the inlet branch between the first valve and a second valve, the other end of the heat exchanger pipeline is connected to the first pipeline between the pipeline valve and the outlet branch, and a heat source valve is arranged on a heat source pipeline between the inlet branch and the outlet branch. The heat exchange system can keep the pipe full of heat source at any time, and ensures high-temperature sterilization in the pipe.

Description

Technical Field

[0001] This invention relates to a heat exchange system, and more particularly to an intelligent control heat source heat exchange system. Background Technology

[0002] Currently, heat sources for heat exchange systems are diverse, including solar energy, boiler hot water or steam, boiler waste heat, and so on. Solar energy is a clean and inexhaustible energy source with enormous reserves; the total amount of solar radiation received annually on the Earth's surface is 1 × 10⁻⁶. 18 The solar energy density (kW·h) is more than ten thousand times the world's total annual energy consumption. However, due to the low energy density of solar radiation reaching the Earth (approximately one kilowatt per square meter) and its discontinuous nature, large-scale development and utilization face certain difficulties. Therefore, to widely utilize solar energy, not only technical problems must be solved, but it must also be economically competitive with conventional energy sources. Various industrial parks are scattered around cities in my country. Heat resources are commonly found in industrial production processes, especially in industries such as metallurgy, chemicals, petroleum, building materials, glass, and papermaking. Currently, industrial waste heat is dissipated into the atmosphere through cooling systems within the factories. Statistics show that nearly two-thirds of this waste heat is not effectively utilized, consuming a large amount of energy in the industrial sector, with most of it ultimately being emitted as hot water and flue gas, resulting in energy waste.

[0003] A heating network, also known as a heating pipeline, refers to the heating pipelines that run from boiler rooms, direct-fired turbine rooms, heating centers, etc., from heat sources to the heating inlets of buildings. Multiple heating pipelines form a network. The design of heating networks is as follows: the design pressure of the heating hot water medium is less than or equal to 2.5 MPa, and the design temperature is less than or equal to 200℃; the design pressure of the heating steam medium is less than or equal to 1.6 MPa, and the design temperature is less than or equal to 350℃. Currently, during heating, individual households generally use heat exchangers for heat exchange and heating.

[0004] Shell-and-tube heat exchangers, also known as tubular heat exchangers, are indirect heat exchangers that use the walls of tube bundles enclosed in a shell as the heat transfer surface. These heat exchangers have a relatively simple structure, reliable operation, and can be manufactured using various structural materials (mainly metals). They can be used under high temperature and high pressure conditions and are currently the most widely used type.

[0005] Shell-and-tube heat exchangers are widely used in industries such as chemical, petroleum, refrigeration, nuclear power, and energy. Due to the global energy crisis, the demand for heat exchangers in industrial production is increasing, and the quality requirements for heat exchangers are also becoming more stringent. In recent decades, although compact heat exchangers (plate, plate-fin, and welded plate heat exchangers, etc.), heat pipe heat exchangers, and direct contact heat exchangers have developed rapidly, shell-and-tube heat exchangers still dominate in terms of production and usage due to their high reliability and wide adaptability. According to relevant statistics, shell-and-tube heat exchangers still account for about 70% of all heat exchangers used in industrial installations.

[0006] The current shell-and-tube heat exchanger thermal system has the following problems: the flow direction at the inlet and outlet of the shell-and-tube heat exchanger cannot be changed; when the shell-and-tube heat exchanger is not in use, no fluid flows through it, which makes it easy for bacteria to grow, especially for shell-and-tube heat exchangers for domestic water. At the same time, the descaling effect of the shell-and-tube heat exchanger is not good, and it is impossible to remove the scale in the tubes in time.

[0007] In response to the above findings, this invention has been improved by adopting a novel heat source heat exchange system. This system can solve at least one of the problems of shell-side inlet direction change, ensuring sterilization within the heat exchanger, and maintaining good descaling. Summary of the Invention

[0008] To achieve the above objectives, the technical solution of the present invention is as follows: A smart control heat source heat exchange system includes a heat source pipeline, an inlet branch and an outlet branch connected to the inlet and outlet of the heat source pipeline, a first valve and a second valve installed on the inlet branch, the first valve being upstream of the second valve, an outlet valve installed on the outlet branch, a first pipeline connected between the upstream of the first valve on the inlet branch and the upstream of the outlet valve on the outlet branch, and a pipeline valve installed on the first pipeline; the system also includes a heat exchanger pipeline, a heat exchanger installed on the heat exchanger pipeline, one end of the heat exchanger pipeline being connected to the inlet branch between the first valve and the second valve, and the other end being connected to the first pipeline between the pipeline valve and the outlet branch, and a heat source valve installed on the heat source pipeline between the inlet branch and the outlet branch.

[0009] Preferably, the heat exchanger is a shell-and-tube heat exchanger, and the heat source passes through the tube side of the heat exchanger.

[0010] Preferably, the heat exchanger is provided with a shell-side inlet valve and a shell-side outlet valve, respectively.

[0011] Preferably, when a heat source is required, the controller closes the heat source valve, outlet valve, and first valve, and opens the pipeline valve, second valve, shell-side inlet valve, and shell-side outlet valve. After the heat source is cooled by heat exchanger, it flows out through the end of the inlet branch.

[0012] Preferably, when the heat source is not needed, the controller controls the heat source valve, the second valve, the inlet valve and the shell outlet valve to close, and the outlet valve and the first valve to open. The heat source does not exchange heat through the heat exchanger and flows to the heat source pipeline through the outlet branch.

[0013] Preferably, the first flow mode of the heat source is that the heat source passes through the pipeline valve to the heat exchanger, and then through the second valve, and flows out from the end of the inlet branch. The second flow mode of the heat source is that the heat source passes through the first valve to the heat exchanger, and then flows into the heat source pipeline through the outlet valve. The controller controls the flow of fluid between the first mode and the second mode as needed.

[0014] Preferably, the heat source can be solar-heated hot water, boiler-heated hot water, or flue gas with waste heat.

[0015] Compared with the prior art, the present invention has the following advantages: 1. The heat exchange system of the present invention can keep the tube side full of heat source at all times, ensuring the high-temperature sterilization effect in the tube side.

[0016] 2. The heat exchange system of the present invention can change the inlet and outlet positions of the tube side of the shell-and-tube heat exchanger, so that the temperature of the heating cold source and the cooling heat source can be selected within a certain range. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the heat exchange system structure of the present invention. Detailed Implementation

[0018] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0019] Unless otherwise specified, in this article, " / " represents division, and "×" and "*" represent multiplication.

[0020] Figure 1 A smart control heat source heat exchange system is disclosed. For example... Figure 1As shown, the system includes a heat source pipeline 1, an inlet branch 2 and an outlet branch 3 connected to the inlet and outlet of the heat source pipeline, a first valve 4 and a second valve 5 installed on the inlet branch, the first valve 4 being located upstream of the second valve 5, an outlet valve 6 installed on the outlet branch 3, a first pipeline connected between the upstream of the first valve 4 of the inlet branch 3 and the upstream of the outlet valve of the outlet branch 3, and a pipeline valve 8 installed on the first pipeline; the system also includes a heat exchanger pipeline 9, a heat exchanger 10 installed on the heat exchanger pipeline, one end of the heat exchanger pipeline 10 being connected to the inlet branch 2 between the first valve and the second valve, and the other end being connected to the first pipeline between the pipeline valve and the outlet branch, and a heat source valve 7 installed on the heat source pipeline between the inlet branch and the outlet branch.

[0021] Preferably, when a heat source is needed, the controller closes the heat source valve, outlet valve, and first valve, while opening the pipeline valve, second valve, shell-side inlet valve, and shell-side outlet valve. The heat source, after being cooled by heat exchanger, flows out through the end of the inlet branch. As an improvement, the heat source is hot water or steam, which becomes domestic water after heat exchange.

[0022] Preferably, when the heat source is not needed, the controller controls the heat source valve, the second valve, the inlet valve and the shell outlet valve to close, and the outlet valve and the first valve to open. The heat source does not exchange heat through the heat exchanger and flows to the heat source pipeline through the outlet branch.

[0023] The heat exchange system of the present invention can keep the tube side full of heat source at all times, ensuring the high-temperature sterilization effect in the tube side and improving the quality of domestic water.

[0024] Preferably, the heat exchanger is a shell-and-tube heat exchanger, and the heat source passes through the tube side of the heat exchanger.

[0025] Preferably, the heat exchanger is provided with a shell-side inlet valve 11 and a shell-side outlet valve 12 at the shell-side inlet and shell-side outlet, respectively.

[0026] Preferably, the heat source flow path includes a first flow mode and a second flow mode. In the first flow mode, the pipeline valve and the second valve are open, while the first valve and the outlet valve are closed. In this first flow mode, the heat source passes through the pipeline valve to the heat exchanger, then through the second valve, and flows out from the end of the inlet branch. In the second flow mode, the first valve and the outlet valve are open, while the second valve and the pipeline valve are closed. The heat source passes through the first valve to the heat exchanger, then through the outlet valve and flows into the heat source pipeline. The controller controls the fluid flow between the first and second modes as needed.

[0027] The required descaling can be based on the scaling condition of the heat exchanger tubes. For example, the tubes can be descaled periodically. During the descaling phase, the controller can periodically control the fluid flow between a first mode and a second mode as needed. This allows the heat source to be continuously flushed through the tubes, creating a reciprocating intermittent flow, thus achieving thorough descaling.

[0028] During the descaling stage described above, the heat exchanger can still exchange heat between the heat source and the cold source, and the cold source in the shell side can still be heated normally. Therefore, compared with existing descaling methods, the above descaling mode does not affect the normal use of the heat exchanger.

[0029] Preferably, the heat source can be solar-heated hot water, boiler-heated hot water or steam, or waste heat-heated hot water.

[0030] As an improvement, the required temperature can be determined based on the heating temperature of the cold source. Because the first and second modes of the heat source involve counter-current or co-current heat exchange, the heat exchange effects differ, resulting in different cold source output temperatures. Therefore, if a high cold source output temperature is required, counter-current heat exchange in the first and second modes is selected; if a low cold source output temperature is required, co-current heat exchange in the first and second modes is selected, thereby controlling the cold source output temperature.

[0031] As an improvement, a normal shell-and-tube heat exchanger operates in counter-current mode. During descaling, it switches between counter-current and co-current flow.

[0032] The heat exchanger is arranged vertically, with multiple baffles installed inside the shell. The baffles are arranged horizontally.

[0033] The shell and tube sides flow counter-currently. As an improvement, the baffle spacing increases continuously from the tube inlet to the middle of the tube side along the fluid flow direction. Then, the baffle spacing decreases continuously from the middle of the tube side to the tube outlet. Because the heat transfer per unit length along the fluid flow path is relatively uniform during counter-current flow, the overall heat transfer effect is optimal. However, experiments and simulations have shown that the heat transfer in the middle is significantly greater than that at the tube inlet and outlet. Therefore, by changing the baffle spacing, the heat transfer area between the tube-side fluid and the shell-side fluid in the baffle also changes. This area change compensates for the uneven heat transfer, thereby further improving the heat transfer efficiency.

[0034] As an improvement, along the flow direction of the fluid within the tube, the spacing of the baffles increases progressively from the tube inlet to the middle of the tube. Then, from the middle of the tube to the tube outlet, the spacing of the baffles decreases progressively. This variation in spacing makes the heat transfer per unit length of the fluid flow more uniform, further improving heat transfer efficiency.

[0035] As an improvement, during heat exchange, a portion of the fluid enters the heat exchanger, while a portion does not. When the heat exchange system is performing heat exchange, such as... Figure 1 As shown, shell-side inlet valve 11 and shell-side outlet valve 12 are open, allowing a cold source to flow into heat exchanger 10. Pipeline valve 8 is open, first valve 4 is closed, and second valve 5 is open. The heat source in heat source pipeline 1 flows into pipeline 8 after entering through inlet branch pipe 2. A portion of the heat source flows directly back to heat source pipeline 1 through second branch pipe 3, while the other portion flows into heat exchanger 10 from the top of the heat exchanger for cooling. The cooled heat source flows into inlet branch pipe 2 and then into the water-using equipment from the outlet of inlet branch pipe 2. Because the heat source returning to heat source pipeline 1 is not cooled by heat exchanger 10, it not only reduces the energy consumption of heat exchanger 10 and avoids energy waste, but also prevents the cooled heat source from affecting the water temperature in heat source pipeline 1, thus helping to maintain the water temperature of the heat source in heat source pipeline 1.

[0036] As an improvement, when the heat exchange system stops exchanging heat, such as Figure 1 As shown, shell-side inlet valve 11 and shell-side outlet valve 12 are closed, stopping the flow of cold source into heat exchanger 10. Pipeline valve 8 is closed, first valve 4 is open, and second valve 5 is closed. The heat source in heat source pipeline 1 flows into the heat exchanger pipeline from the inlet branch pipe 1, then enters the heat exchanger 10 through the bottom port, and exits from the top port of the heat exchanger 10 into the outlet branch 3. Finally, the heat source drawn from heat source pipeline 1 flows back into heat source pipeline 1, ensuring that the heat source in the heat source cooling system is always in a circulating state.

[0037] While the present invention has been disclosed above with reference to preferred embodiments, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. An intelligent control heat source heat exchange system, the system comprising a heat source pipeline, an inlet branch and an outlet branch connected to the inlet and outlet of the heat source pipeline, wherein a first valve and a second valve are provided on the inlet branch, the first valve being located upstream of the second valve, an outlet valve is provided on the outlet branch, and a first pipeline is connected between the upstream of the first valve on the inlet branch and the upstream of the outlet valve on the outlet branch, wherein a pipeline valve is provided on the first pipeline. The system also includes a heat exchanger pipeline with a heat exchanger installed on it. One end of the heat exchanger pipeline is connected to the inlet branch between the first valve and the second valve, and the other end is connected to the first pipeline between the pipeline valve and the outlet branch. A heat source valve is installed on the heat source pipeline between the inlet branch and the outlet branch. The heat exchanger is a shell-and-tube heat exchanger, and the heat source in the heat source pipeline passes through the tube side of the heat exchanger. The heat exchanger is arranged vertically, with multiple baffles installed inside the shell and tubes. The baffles are arranged horizontally. The shell side and tube side flow in countercurrent. Along the flow direction of the fluid in the tube side, the spacing between the baffles increases continuously from the tube inlet to the middle of the tube side, and then decreases continuously from the middle of the tube side to the tube outlet.

2. The intelligent control heat source heat exchange system as described in claim 1, characterized in that, The heat exchanger is equipped with a shell-side inlet valve and a shell-side outlet valve, respectively.

3. The intelligent control heat source heat exchange system as described in claim 2, characterized in that, The system includes a controller. When a heat source is needed, the controller controls the heat source valve, outlet valve, and first valve to close, while the pipeline valve, second valve, shell-side inlet valve, and shell-side outlet valve are opened. After the heat source is cooled by heat exchanger, it flows out through the end of the inlet branch.

4. The intelligent control heat source heat exchange system as described in claim 2, characterized in that, The system includes a controller. When the heat source is not needed, the controller controls the heat source valve, the second valve shell-side inlet valve, and the shell-side outlet valve to close, while the outlet valve and the first valve open. The heat source does not undergo heat exchange in the heat exchanger and flows to the heat source pipeline through the outlet branch.

5. The intelligent control heat source heat exchange system as described in claim 1, characterized in that, The heat source can be solar-heated hot water, boiler-heated hot water, or steam.

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